The COMPASS Collaboration performed measurements of the Drell-Yan process in 2015 and 2018 using a 190 GeV/c π^{-} beam impinging on a transversely polarized ammonia target. Combining the data of both years, we present final results on the amplitudes of five azimuthal modulations, which correspond to transverse-spin-dependent azimuthal asymmetries (TSAs) in the dimuon production cross section. Three of them probe the nucleon leading-twist Sivers, transversity, and pretzelosity transverse-momentum dependent (TMD) parton distribution functions (PDFs). The other two are induced by subleading effects. These TSAs provide unique new inputs for the study of the nucleon TMD PDFs and their universality properties. In particular, the Sivers TSA observed in this measurement is consistent with the fundamental QCD prediction of a sign change of naive time-reversal-odd TMD PDFs when comparing the Drell-Yan process with deep inelastic scattering. Also, within the context of model predictions, the observed transversity TSA is consistent with the expectation of a sign change for the Boer-Mulders function.

A 1 Alikhanyan National Science Laboratory 2 Alikhanyan Br Street 0036 Yerevan Armenia

Abdus Salam ICTP 34151 Trieste Italy

Academia Sinica Institute of Physics Taipei 11529 Taiwan

Affiliated with an institute covered by a cooperation agreement with CERN

Affiliated with an international laboratory covered by a cooperation agreement with CERN

Center for High Energy and High Field Physics and Dept of Physics National Central University 300 Zhongda Rd Zhongli 320317 Taiwan

CERN 1211 Geneva 23 Switzerland

Charles University Faculty of Mathematics and Physics 12116 Prague Czech Republic

Czech Technical University Prague 16636 Prague Czech Republic

Institute of Scientific Instruments of the CAS 61264 Brno Czech Republic

IRFU CEA Université Paris Saclay 91191 Gif sur Yvette France

LIP 1649 003 Lisbon Portugal

Ludwig Maximilians Universität 80539 München Germany

Matrivani Institute of Experimental Research and Education Calcutta 700 030 India

National Centre for Nuclear Research 02 093 Warsaw Poland

Technical University in Liberec 46117 Liberec Czech Republic

Technische Universität München Physik Dept 85748 Garching Germany

Tel Aviv University School of Physics and Astronomy 69978 Tel Aviv Israel

Torino Section of INFN 10125 Torino Italy

Trieste Section of INFN 34127 Trieste Italy

Universität Bochum Institut für Experimentalphysik 44780 Bochum Germany

Universität Bonn Helmholtz Institut für Strahlen und Kernphysik 53115 Bonn Germany

Universität Bonn Physikalisches Institut 53115 Bonn Germany

Universität Freiburg Physikalisches Institut 79104 Freiburg Germany

Universität Mainz Institut für Kernphysik 55099 Mainz Germany

University of Aveiro I3N Dept of Physics 3810 193 Aveiro Portugal

University of Illinois at Urbana Champaign Dept of Physics Urbana Illinois 61801 3080 USA

University of Miyazaki Miyazaki 889 2192 Japan

University of Torino Dept of Physics 10125 Torino Italy

University of Trieste Dept of Physics 34127 Trieste Italy

University of Warsaw Faculty of Physics 02 093 Warsaw Poland

Warsaw University of Technology Institute of Radioelectronics 00 665 Warsaw Poland

Yamagata University Yamagata 992 8510 Japan

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